Furnace and burner unit



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FURNACE AND BURNER UNIT 2 Sheets-Sheet 1 Filed Dec. 30, 1963 Frank W Kejnonen Haber? Z: Nag fer INVENTORS H rs.

1966 F. w. KEINONEN ETAL FURNACE AND BURNER UNIT 2 Sheets-Sheet 2 Filed Dec. 30, 1963 n S m P m ,T o k m .mgw za 6 a w a K N 1 J W E k w n e Z Y a F E ii P l LA J fmsv .QV WNQW ww A EEEEEEQ I United States Patent 3,285,318 FURNACE AND BURNER UNIT Frank W. Keinonen, Portland, and Robert E. Nagler,

Tigard, 0reg., assignors, by mesne assignments, to Pioneer Manufacturing Co., City of Industry, Calif., a corporation of California Filed Dec. 30, 1963, Ser. No. 334,456 4 Claims. (Cl. 158-114) This invention relates to furnaces and like appliances, and a construction for burner units therein.

More specifically, the invention relates to a burner unit for gas furnaces, featuring novel improvements whereby the same is an efficient and reliably operating unit, the unit at the same time being simply constructed and produceable at relatively low cost.

One form of gas furnace known today comprises a heat exchanger, with elongated furnace chambers therein where fuel combustion takes place. Means is provided for circulating air through passages in the exchanger, and such air is warmed in the exchanger, whence it is blown into the space to be heated. Elongated burners, sometimes referred to as pipe-type burners, are included in the furnace, and these extend into the furnace chambers mentioned, and supply the fuel which is ignited during operation of the furnace.

With gas furnaces, particularly those including pipetype burners of the type described, problems are involved in obtaining a proper fuel mixture for burning, and in properly circulating the fuel mixture to the burners prior to combustion actually taking place. Most furnaces are operated intermittently, and there are also problems involved in providing for quick-acting and reliable start-up in the furnace after a nonoperating period.

A general object of this invention is to provide a novel burner unit for gas furnaces, and related heating" appliances, which takes care of the above mentioned difficulties in a highly satisfactory and practical manner.

More specifically, an object is to provide a burner unit, which includes multiple, elongated burners for injecting a fuel mixture in the zones where combustion actually takes place and a novel flame carry-over means interconnecting these burners whereby all may be ignited quickly and surely from a pilot burner located adjacent the burner unit.

Another object is to provide a burner unit, including multiple burners and novel flame carry-over means for igniting the burners, which includes means effective to produce a positive gas pressure in the carry-over means during start-up periods.

A further specific object is to provide a novel burner unit, with multiple pipe-type burners, which includes multiple fuel mixing cavities for mixing gas and air for burning, one for each burner, and novel means accommodating a change in amount of air mixed with the gas, whereby a proper consistency in the fuel mixture may be produced.

Other and related features of the invention include the provision of a novel burner unit which is adapted to be manufactured from stamped metal parts. Considerable economies may thus be realized in the production of the burner units.

The burner unit of the invention is particularly advantageously incorporated in a furnace of the type which has a series of adjacent furnace chambers or compartments defined in a heat exchanger, since the construction of the unit is such as to readily accommodate an increase or decrease in the heating capacity of the furnace, by increasing or decreasing the number of burners included in the burner unit.

While the invention is described hereinbelow in connection with a gas fired, hot-air furnace, it is not intended 3,285,318 Patented Nov. 15, 1966 thereby to limit the invention solely to such apparatus, as certain features of the invention have applicability to other end related heating appliances.

The invention is described hereinbelow and in conjunction with accompanying drawings, wherein:

FIG. 1 is a perspective view, illustrating a furnace constructed according to one embodiment of this invention;

FIG. 2 is a plan view, on a slightly enlarged scale, showing a burner unit as contemplated herein including a pair of pipe-type burners;

FIG. 3 is a side elevation of the burner unit in FIG. 2 with portions thereof broken away;

FIG. 4 is a cross sectional view taken along the line 44 in FIG. 2;

FIG. 5 is a cross sectional view along the line 55 in FIG. 2;

FIG. 6 is a cross sectional view along the line 66 in FIG. 2;

FIG. 7 is a perspective view on a still larger scale, showing a damper element present in the furnace unit; and

FIG. 8 is another perspective view, on approximately the same scale as FIG. 7, showing a baffle element present in the burner unit.

Referring now to the drawings, and first of all more particularly to FIG. 1, here a furnace is indicated generally at 10, including a substantially rectangular cabinet 12 which houses the operating parts of the furnace.

Mounted within cabinet 12, substantially midway between the top and bottom ends thereof, is a heat exchanger 14. Heat exchanger 14 includes walls 15 defining a pair of elongated furnace chambers 16 and 18 which extend to the rear of the heat exchanger. Air to be heated passes upwardly into the heat exchanger through a duct 20. Such air circulates through passages in the heat exchanger (not shown) where it is heated. The air leaves the heat exchanger and the furnace through a duct 22.

Heat exchanger 14 including its walls 15 are heated by means of a burner unit, shown generally at 24. As best seen in FIG. 2, burner unit 24 includes a pair of elongated, pipe-type burners designated at 26 and 28. Each burner extends rearwardly in the heat exchanger in one of the furnace chambers 16, 18, shown in FIG. 1. A fuel mixture is supplied to burner elements 26, 28 through a manifold 30. In FIG. 1 the manifold is illustrated, but details of the burners have been omitted since the scale of the drawing does not permit the showing of such details.

Still referring to FIG. 1, valve mechanism 32 including valve casing 32' is illustrated, which is suitably connected to a fuel gas supply line (not shown). Valve mechanism 32 controls the supply of fuel, through a conduit 32, to manifold 30. At 34 is indicated a line which is connected to a thermo-sensitive device (not illustrated) operable to adjust valve mechanism 32 so as to close off the supply of gas to manifold 30 should a pilot burner for the furnace happen inadvertently to become extinguished. Such a pilot burner, shown at 35 in FIG. 2, is supplied fuel through line 36.

In the furnace illustrated, as already indicated, there are a pair of burners 26, 28, and these extend into a heat exchanger having a pair of furnace chambers 16 and 18. Thus the furnace illustrated has a relatively low heat capacity, and would be used for heating arelatively small space. Where a larger heat output is desired, a larger heat exchanger may be provided, including a greater number of furnace chambers. With such a heat exchanger, a burner unit is used which includes a correspondingly greater number of burners. A feature of the invention is that the construction of burner unit 24 is such as to permit readily modification by changing the number of burners therein to make the same adaptable for furnaces of varying capacities.

Burner unit 24 is illustrated in more detail, and on a slightly enlarged scale, in FIGS. 2- through 6.

Referring now to FIGS. 2 and 3, it will be noted that the burner unit illustrated comprises a body formed of a pair of shaped plates, which may be metal stampings, and which are indicated at 40, 42. Plates 40, 42 are mounted in face-to-face relationship. Each of the plates includes a pair of elongated projections, indicated for upper plate 40 at 40a and 40b. The projections of the upper plate, i.e., projections 40a and 401), are opposite similar projections provided in the lower plate. The two projections of a plate are shaped with a transverse concavity, and this concavity faces a similar transverse concavity shaped in the projections of the other plate. Along the margins of the concavity in the various projections are marginal flanges, indicated for top plate 40 at 45, and for the bottom plate 42 at 47. In the burner unit, these margins are joined together in a suitable manner. The projections, with their concavities, form elongated, hollow, substantially parallel finger elements, and these finger elements are the burners 26, 28 in the unit.

Each of the burners has a row of jet apertures 46 provided along the length thereof. The apertures, which accommodate the flow of streams of fuel for ignition purposes from the burners, comprise cut outs made in top plate 40.

The body of the burner unit, in addition to the burners described, includes what is referred to herein as a base portion 50. The burners or finger elements project to one side of base portion 50. Base portion 50 is formed by expanse 52 of plate 40, and expanse 54 of plate 42.

Expanses 52, 54 of plates 40, 42 are each provided with shaped portions that define a fuel transfer passage connecting with the interior of each burner. Thus, and considering burner 26, an elongated concavely curved portion 56 is provided in plate 40, and a similar concavely curved portion 58 is provided in plate 42. These two curved portions together define a fuel transfer passage 6Q which flares progressing from left to right in FIG. 3. This passage 60 communicates with the hollow interior of burner 26. Similar curved portions define a'similar fuel transfer passage for burner 28.

Expanses 52, 54 of upper and lower plates 40, 42 are also formed with circular skirt portions defining a fuel mixing cavity communicating with each transfer passage. This is illustrated for transfer passage 60, (connecting with burner 26) by skirt portions 62, 64 shown adjacent the right edge of base portion 50. Skirt portions 62, 64 are bounded by circular edges 66, 68 which define openings on the top and bottom of the burner unit. The mixing cavity defined by skirt portions 62, 64 is indicated at 70 and it will be noted that the cavity has a generally spherical over-all outline truncated by cut-off planes disposed on opposite sides of the cavity, which cut-01f planes generally parallel the longitudinally axes of burners 26, 28 and the plane in which these burners extend. The mixing cavity communicates with the small diameter end .of passage 60. As illustrated in the drawings, similar skirt portions define a similar fuel mixing cavity for the passage corresponding to passage 60 which communicates with burner 28.

Plate expanses 52, 54 further include semicylindrically formed portions, illustrated by portions 72, 74 for mixing cavity 70, which together define a cylindrical tube section projecting out from one side of each cavity.

A combustible fuel mixture is supplied each burner from the fuel mixing cavity associated with the burner. Each mixing cavity has a separate means for introducing a supply of gas thereto. Thus, and considering burner 26, a nozzle is illustrated at 80, containing the usual aperture 81 accommodating the flow of gas from the nozzle. The nozzle is mounted on manifold 30, with the inside of the nozzle communicating with the inside of the mani- ,unit by edges 66, 68 of a set of skirt portions 62, 64.

According to this invention, a damper element 86 is pro vided in each mixing cavity, illustrated in perspective in FIG. 7, for the purpose of regulating the amount of air mixed with the gas.

Each damper element is hollow and has a substantially spherical outline, as most clearly seen in FIG. 7 which matches the outline of the mixing cavity within which the damper element is mounted. The spherical outline of each damper element is truncated along opposite sides in parallel planes in a manner which resembles the truncation of the mixing cavities earlier described. The damper element includes arced-arms 87, 88, which with the element properly mounted in a mixing cavity, are positioned snugly beside the walls of the cavity. A curved web portion 90 joins the arced-arrns, and this web portion con tains a circular hole 92.

With a damper element mounted in place, within a mixing cavity, hole 92 accommodates the nozzle for the cavity, said nozzle extending from the manifold and past the damper element into the mixing cavity. As best seen in FIG. 6, because the damper element has a spherical overall outline, it has circular outline in a plane extending transversely of the nozzle which extends through it. The mixing cavity surrounding the damper element has a matching circular outline in this transverse plane. This means that the damper element may be rotated about an axis extending normal to this transverse plane, or about an axis which substantially corresponds to the longitudinal axis of the nozzle. By rotating the damper element in the directions indicated by the double pointed arrow shown in FIG. 6, the openings at the top and bottom of a mixing cavity may be closed to a varying extent by the arms of the damper element. It is in this way that a proper consistency is produceable in the fuel ted to the burners, whereby complete and economical combustion may be obtained.

As noted earlier, in FIG. 2 a pilot burner is shown at 35, which is utilized to ignite ga emanating from the burner unit on start-up after a nonoperating period. The pilot burner is conventional, and includes the usual orifice through which a small stream of gas is continuously ejected. This gas stream burns continuously, whereby a small flame is always present over the series of ports 46 present in burner 28 illustrated at the top of FIG. 2. A feature of this invention is the provision of novel carryover means, whereby a flame is carried from one to other .burners in the burner unit, in a reliable and speed manner, upon fuel being supplied simultaneously to all the burners. In this way the unit is made quickly operative, after a nonoperating period.

Referring now to FIGS. 2, 3, and 5, it will be noted that top and bottom plates 40, 42 include oppositely disposed concave portions, indicated at and 102, respectively. These concave portions define a carry-over passage 104, also referred to herein as a bleed passage, which extends between and interconnects interiors of the burners, at points adjacent the butt ends of these burners. As best seen in FIG. 5, by the outer contour shown for portions 100, 102, passage 104, progressing from one burner to the other, gradually decreases in size and has its smallest cross section at a point approximately midway between the two burners.

Upper plate 40 contains a series of small apertures or orifices 106, constituting aperture means herein, disposed in a row along the top of concave portion 100, said row thus extending transversely of the burners in the space between the burners. These orifices accommodate the flow of gas in streams from inside the carry-over passage to the exterior of the burner unit, with such gas streams ejecting into the atmosphere at points distributed between the burners.

When gas is fed to the burner unit from manifold 30, through nozzles 80, 82, such gas flow through the fuel transfer passages, and a portion of the gas supplied by each nozzle flows into one end of the carry-over passage, when it flows out orifices 106 as described. With the pilot burner operating, this gas is ignited, to produce a carry-over flame xtending between adjacent burners.

In the burner unit, particularly if the nozzles are not exactly properly positioned, so as to direct gas directly forwardly into the burners in front thereof, with the construction so far described, a subatmospheric pressure may result in carry-over passage 104. Further explaining, a fuel mixture in flowing into the burners and out through ports 46 may produce a suction in opposite ends of passage 104, whereby air is drawn into the passage through orifices 106. Any such tendency, of course, is undesirable, as it prevents the carry-over passage described from operating properly. Thus bafile elements are included in the burner unit, one for each burner, which function positively channel a small amount of gas into opposite ends of interconnecting passage 104, whereby such a subatmospheric condition is prevented.

Referring to FIGS. 3, 5, and 8, a bafile element is shown at 110. The bafile element is hollow, with open ends, and approximately cylindrical in shape. The batfle element for a burner is mounted inside the burner adjacent its butt end, at the location where interconnecting passage 104 has an end connecting with the interior of the burner.

As seen in FIG. 8, each baifle element includes a top and a bottom 112, 114, respectively, and arcuately curved sides 116, 118, 120 and 122. With the baflie element properly in place within a burner, these sides are spaced somewhat inwardly from those. portions of plates 40, 42 which define the burner and the passage 60 extending into the burner. The forward end of a baffie element, i.e., the end nearest the viewer in FIG. 8, includes flange means 124, which extends substantially entirely around the end of the element, save for a cut-out portion 126. This flange means, as can be seen in FIG. 3, rests snugly against top and bottom plates 40, 42 in the completed burner unit.

Each bafile element is operable to define two channels 140, 142 extending forwardly from the passage 60 behind it. One of these channels extends along the interior of the bafile element, and leads to the hollow burner in front of the bafile element. This channel accommodates the flow of the major portion of the fuel mixture flowing in passage 60. The other channel comprises the annular channel extending about the baffle element. This channel is blocked at its forward end by flange means 124, and connects with an end of interconnecting passage 104.

The baflle element includes a flap 128 which seats within a slot 130 cut in plate 40. This flap serves to position the bafile element properly in the unit. Dimples 132 adjacent an end of element opposite flange 124 function to position this end of the baflle element in the assembly. Oppositely disposed flanges 134, 136 extending along the length of the element also function to position the element. These flanges may be joined, if desired, as by welding, to one of the plates 40, 42, to anchor the element in place.

Each bafile element, by defining a pair of channels extending longitudinally of passage 60, operates to divert a small portion of the gas flowing through passage 60, and channel this gas into interconnecting passage 104.

During operating periods, a combustible mixture, i.e., gas and a certain amount of air, is supplied each burner from a separate nozzle located to the rear thereof. Com- 6 bustion of this mixture takes places substantially along the entire length of each burner. When starting up after a period of nonoperattion, there is a substantially immediate and positively produced discharge of gas through orifices 106. This gas is quickly ignited to produce a carry-over flame from one burner to the next.

A proper fuel mixture is readily produceable by suitable adjustment of damper elements 86 provided for the respective burners.

The construction may be readily modified to adapt it for larger capacity. This is done by increasing the number of burners formed .by plates 40, 42.

The unitized construction contemplated makes the burner unit easy to install, and easy to remove if replacement is necessary. The plate construction of the unit enables the unit to be manufactured at low cost.

While there has been described an embodiment of the invention, variations and modifications are possible. It is not intended to be limited in all respects to the specific embodiment disclosed, as it is desired to cover all variations and modifications as would be apparent to one skilled in the art, and that come within the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. In a burner unit,

a body with an elongated burner passage defined therein and a jet opening in said body connecting with said burner passage accommodating the flow for ignition purposes of a fuel mixture from said burner passage,

a fuel mixing cavity defined in said body where fuel is mixed with air, said cavity being spaced from one end of said burner passage,

a fuel transfer passage defined within said body extending from said fuel mixing cavity to said one end of said burner passage,

a bleed passage defined in said body extending laterally of said fuel transfer passage, communicating at one end with said fuel transfer passage,

an aperture in said body connecting said bleed passage with the atmosphere and accommodating the flow of a fuel mixture from said bleed passage to the atmosphere, and

a substantially cylindrically shaped hollow baflle element mounted within said fuel transfer passage, with the axis thereof substantially paralleling the longi tudinal axis of said burner passage and with the inside thereof forming a path between said fuel mixing cavity and said burner passage, said bafiie element being mounted in said fuel transfer passage adjacent where the bleed passage connects with the transfer passage and including means on the outside thereof blocking the flow of the fuel mixture whereby such is directed on flowing over the outside of the baflle element into said bleed passage.

2. In a burner unit,

a body with an elongated burner passage defined therein, and a jet opening in said body connecting with said burner passage accommodating the flow for ignition purposes of a fuel mixture from said burner passage,

a fuel mixing cavity defined in said body where fuel is mixed with air, said cavity being spaced from one end of said burner passage,

an elongated fuel transfer passage defined within said body extending from said fuel mixing cavity to said one end of said burner passage, said fuel mixing cavity having a spherical outline truncated by a cut-off plane along at least one side thereof which plane substantially parallels the longitudinal axis of said fuel transfer passage,

an opening for the fuel mixing cavity defined where the same is truncated by said cut-off plane which faces laterally to one side of the fuel transfer passage, and

a hollow damper element mounted within the fuel mixing cavity, having a spherical outline which matches the spherical outline of the mixing cavity, said damper element being rotatable about an axis generally paralleling the longitudinal axis of the transfer passage and having means defining an opening 8 gated projections, disposed opposite similar projections in the other plate, each of the projections of one plate having a transverse concavity that faces a similar transverse concavity in the projection of the thereinto accommodating the flow of air into said mixother plate which is opposite it,

ing cavity which is registrable with said opening of the said projections of the two plates cooperating to form fuel mixing cavity to varying degrees depending upon elongated hollow fingers in the unit which taper prothe position that the damper element occupies relagressing from aset of adjacent butt ends,

tive to said opening of said fuel mixing cavity. each of said plates further including an expanse join- 3. Ina burner unit, 10 ing the projections of the plate which is opposite and a body with an elongated burner having a passage defacing a similar expanse in the other plate, said exfined therein, and a jet opening in said body connectpanses of the two plates having formed portions deing with said burner passage accommodating the fiow fining a pair of fuel transfer passages, one connecting for ignition purposes of a stream of fuel from said with each hollow finger, and burner passage, a baffie element for each hollow finger, mounted bea fuel mixing cavity defined in said body where fuel tween said expanses of the two plates, in the transfer is mixed with air, said cavity being spaced from one passage for the finger, adjacent the butt end of the end of said burner passage, finger, said baffle element defining two channels with a fuel transfer passage defined within said body extendone of the two channels connecting with the interior ing from said fuel mixing cavity to said one end of of the finger, and the other channel blocked off from said burner passage, the interior of the finger,

a baflie'within said fuel transfer as age, aid baflie said two plates also having concavely curved portions defining a side channel which has a forw d d in said expanses of the two plates defining a carryblocked off from the burner, over passage which communicates at opposite ends a bleed passage defined in said body which extends latth ai ot c annels defined by the baflle eleerally of said burner passage adjacent its said one mentspfor the two fingersend, said bleed passage connecting with said side h l d References Cited by the Examiner an aperture in said body connecting with said bleed UNITED STATES PATENTS P g sa1d aperture g at a p n l p sed o 1,536,590 5/1925 Kielberg one side of sa1d burner passage, sa1d aperture ac- 1841524 1/1932 Daane 158 x commodating the flow of a fuel mixture from said 1942397 1/1934 C 1 bleed assa e to the atmos here. er 158-404 P g P 2,470,881 5/1949 Zlmbelman 15s 104 X 4. A burner 'llI11lZ.COInpI1SlI1g a pair of shaped plates of 35 2,607,405 v 8/1952 Weinandy 158*116 substantially matching outline oined together with the 3,092,169 6/1963 Lehman plates in face to face relationship,

each of said plates including at least a pair of elon- FREDERICK L. MATTESON, JR., Primary Examiner. 

1. IN A BURNER UNIT, A BODY WITH AN ELONGATED BURNER PASSAGE DEFINED THEREIN AND A JET JOINING IN SAID BODY CONNECTING WITH SAID BURNER PASSAGE ACCOMMODATING THE FLOW FOR IGNITION PURPOSE OF A FUEL MIXTURE FROM SAID BURNER PASSAGE, A FUEL MIXING CAVITY DEFINED IN SAID BODY WHERE FUEL IS MIXED WITH AIR, SAID CAVITY BEING SPACED FROM ONE END OF SAID BURNER PASSAGE, A FUEL TRANSFER PASSAGE DEFINED WITHIN SAID BODY EXTENDING FROM SAID FUEL MIXING CAVITY TO SAID ONE END OF SAID BURNER PASSAGE, A BLEED PASSAGE DEFINED A SAID BODY EXTENDING LATERALLY OF SAID FUEL TRANSFER PASSAGE, COMMUNICATING AT ONE END WITH SAID FUEL TRANSFER PASSAGE, AN APERTURE IN SAID BODY CONNECTING SAID BLEED PASSAGE WITH THE ATMOSPHERE AND ACCOMMODATING THE FLOW OF A FUEL MIXTURE FROM SAID BLEED PASSAGE TO THE ATMOSPHERE, AND A SUBSTANTIALLY CYLINDRICALLY SHAPED HOLLOW BAFFLE ELEMENT MOUNTED WITHIN SAID FUEL TRANSFER PASSAGE, WITH THE AXIS THEREOF SUBSTANTIALLY PARALLEL THE LONGITUDINAL AXIS OF SAID BURNER PASSAGE AND WITH THE INSIDE THEREOF FORMING A PATH BETWEEN SAID FUEL MIXING CAVITY AND SAID BURNER PASSAGE, SAID BAFFLE ELEMENT BEING MOUNTED IN SAID FUEL TRANSFER PASSAGE ADJACENT WHERE THE BLEED PASSAGE CONNECTS WITH THE TRANSFER PASSAGE AND INCLUDING MEANS ON THE OUTSIDE THEREOF BLOCKING THE FLOW OF THE FUEL MIXTURE WHEREBY SUCH IS DIRECTED ON FLOWING OVER THE OUTSIDE OF THE BAFFLE ELEMENT INTO SAID BLEED PASSAGE. 